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Biofortification of wheat with selenium to increase human dietary intake - LK0974

Description
The selenium intake level of the UK population has fallen significantly over the past 30 years. This is from the UK Reference Nutrient Intake (RNI) level of 60-75 µg d-1 in 1974 to less than 35 µg d-1 in 1999 (MAFF 1999) (Figure 1). More recent data suggest that in some poorer demographic areas of the UK this level may be as low as 15µg d-1 (Prof. Fairweather-Tait (IFR), pers. comm.). The degree of concern over Se levels in the UK population has led the Food Standards Agency (FSA) to commission ongoing research within its ‘Optimal Nutrition Programme’ to quantify the beneficial effects of increasing Se intake in adults through human intervention trials

Historically, the main source of Se in the UK diet has been from bread products. The main reason for the reduction in Se intake in the UK is the result of changes in the source of flour for bread-making from North America to European wheat due to economic and consumer demands. The use of UK wheats in grists has risen from 15% in the 1950’s to over 80% in 2005 (Arable Framing 6th June, 2005). Studies have shown that levels of Se in UK bread-making wheat are up to 50 times lower than their North American and Canadian counterparts (Lyons et al., 2003), the primary reason for these differences being the higher levels of Se in American and Canadian soils as compared with UK soils. More recently, the levels of Se in UK soils have declined still further as a result of changes in fertiliser practice (e.g. replacing single superphosphate with triple superphosphate) and reduced industrial emissions.

There are two main routes to increasing the intake of Se. The first is through supplementation the second is through the diet.
Supplementation is a viable option, however, supplements are expensive and only a small proportion of the population would be likely to take a personal intervention measure, particularly in the most vulnerable groups. Therefore the number of people benefiting would be small. Supplements generally provide an Se intake level of 200 µg d-1, the upper safe limit is estimated to be 400 µg d-1 although under normal conditions, a Se intake level of <1,000 µg d-1 has been shown not to cause toxicity (Neve, 1991). Despite this, supplementation may be under threat in the near future due to the EU Food Supplements directive which comes into force in August 2005. Some Se supplements have already been restricted in the livestock sector and it is likely that many in the human supplement sector will be banned.
Objective
This project tests the hypothesis that the Selenium levels of UK wheat can be increased through agronomic biofortification and plant genotype selection.
Selenium biofortified wheat will add value to UK grain, bread products and morning goods thereby providing the potential to significantly increase the dietary intake of selenium and hence improve human health.
Time-Scale and Cost
From: 2005

To: 2009

Cost: £357,931
Contractor / Funded Organisations
Velcourt Ltd, Scottish Crop Research Institute, Nickerson UK Ltd, Carrs Agricultural Ltd, Rothamsted Research (BBSRC), IFR - Institute of Food Research (BBSRC), University - Nottingham, Marks and Spencer plc, Yara (UK) Ltd, Velcourt Ltd (Farm Management)
Keywords
Arable Farming              
Crop Improvement              
Farming              
Wheat Production              
Fields of Study
Resource Efficient and Resilient Food Chain